One Way To Control Common Pond Snails Choking Your System: Assassin Snails

Pond Snail Cure:   The playing field in the battle against invasive small pond snails changed dramatically when the Assassin Snail entered the battle. They’re a tropical snail, so their population is limited by a season in most places. (Won’t overwinter most places)

A small hand full of these Assassin snails would be more than enough to clear the average residential pond under 2-3k gallons. The other really cool thing about them, is that once all the nuisance common pond snails are gone, the Assassin Snail population drops off too. In other words, without PREY, they don’t become a new problem. They can also get fairly large, (2 inches) so they don’t get into the pumps like those stupid little Common pond snails do.

My last, next most favorite thing, is that for most pond keepers, Assassin Snails make a great birthday present. Hahahha! In other words, if you ever have too many, put a note in your Pond club newsletter and bunches of other people will gladly come in remove them for you.

Where to get Assassin Snails, about 3$ each.

What’s the dose of Assassin Snails?

4-5 snails per 100-200 gallons minimum. Some people would hold that for eradication of Lymneid snails in a Big Hurry would use at least a hundred in 1-2K gallons. Yeah that’s a lot of money.


My method was to semi-crush (just crush enough that it remains intact) one medium garlic clove per 40L/10G and leave it in for 12-24 hours before replacing. 50% water change on 3rd day. I’ve only needed to use garlic for about three days before noting a rapid improvement. The water will absolutely stink of garlic.

Garlic juice will not kill the fish, but I recommend you do research because it might kill some types. Add enough garlic so that the water smells slightly of garlic, and yes, the heater can be on.

“If you can’t smell it, it isn’t enough and won’t work.”

The best way to use Garlic is to take a medium clove per 10-20 gallons and put the Garlic in a “nutribullet” and blend the shite out of it. Emulsify it. Then dilute it with water and distribute that around the tank or pond. If you cannot smell it EASILY then it won’t work and you didn’t add enough.”

Fish that LOVE to eat snails if you live in a warm / tropical area of the USA

  • Botia Sidthimunki
  • Dwarf Pygmy Chain Loach
  • Botia Striata

BUT NOT CLown Loach or Yoyo Botia they are TOO aggressive to other fish and will eat goldfish eyeballs.

Lymnaea Stagnalis is the common Snail.


I’m not crazy about this, partly because it kills the shite out of plants, but it’s dangerous to the fish! … so I’m not giving you a dose, but would instead suggest you “get somebody” to do the copper or research it thoroughly. There are difference in total copper and “ionized” copper. And, water hardness differentially affects the toxicity, sometimes drastically.

“It is well known that the lethal dose 96hr-LC50 (20C) for pond snails is 0.39 mg/L (or 0.39 ppm). This means that a concentration of 0.39 parts per million of copper sulfate in your tank will kill half of the snails present over a period of 96 hours if the temperature is kept constant at 20 ⁰C (68 ⁰F).”

You can rear some Sunfish, and they’ll eat every last snail. They use Sunfish for this in North Carolina at my favorite hatchery AND this prevents unauthorized goldfish reproduction AND also controls tadpoles. But I don’t know how they’ll treat your other fish. You can read this about the specifics of the various little sunfish and stuff, written by some guys over at the Fisheries department.

Snail Management in Culture Ponds


Author: Admin